Administering influenza vaccine to egg-allergic persons

Abstract

The most serious form of type I or IgE-mediated hypersensitivity reaction is anaphylaxis. A standardized case definition of anaphylaxis as an adverse event after immunization has been developed. Such reactions to vaccines, including influenza vaccine, are rare but potentially life-threatening. Until recently, all influenza vaccines were manufactured in eggs. Residual egg protein in the vaccines was thought to pose a risk to egg-allergic vaccine recipients. However, a large number of recent studies have demonstrated that egg-allergic recipients are no more likely than those without egg allergy to suffer such reactions. Published guidelines have been updated to recommend that patients with egg allergy receive annual influenza vaccination. Any patient who has an anaphylactic reaction to influenza vaccine should be carefully evaluated by an allergist for guidance on subsequent immunization.

Keywords::

• allergy
• egg allergy
• hypersensitivity
• immunization
• influenza
• vaccination

Financial & competing interests disclosure

The author has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Anaphylactic reactions after influenza vaccination are rare, less than one per million doses.

• Such reactions are no more common in egg-allergic recipients, and patients with egg allergy should receive annual influenza vaccination to protect them from the morbidity and mortality associated with the disease.

• Careful evaluation of allergic reactions to influenza vaccine in individual recipients may identify culprit allergens to inform more cautious subsequent vaccination.